Exhaust aftertreatment system diagnostic and conditioning

ABSTRACT

An engine diagnostic tool includes a diagnostic engine calibration module structured to include a plurality of diagnostic processes for operating an internal combustion engine system of an immobilized vehicle. One or more of the plurality of diagnostic processes are structured to be an intrusive diagnostic process for the internal combustion engine system, wherein the intrusive diagnostic process causes the internal combustion engine system to operate outside of one or more calibration parameters. The diagnostic engine module is further structured to control the order and timing of each diagnostic process in the plurality of diagnostic processes.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/270,907 entitled “EXHAUST AFTERTREATMENT SYSTEM DIAGNOSTIC ANDCONDITIONING,” filed May 6, 2014, which claims the benefit of andpriority to U.S. Provisional Patent Application No. 61/821,143 entitled“EXHAUST AFTERTREATMENT SYSTEM DIAGNOSTIC AND CONDITIONING,” filed May8, 2013, both of which are incorporated herein by reference in theirentireties.

BACKGROUND

Emissions regulations for internal combustion engines have become morestringent over recent years. Environmental concerns have motivated theimplementation of stricter emission requirements for internal combustionengines throughout much of the world. Governmental agencies, such as theEnvironmental Protection Agency (EPA) in the United States, carefullymonitor the emission quality of engines and set acceptable emissionstandards, to which all engines must comply. Consequently, the use ofexhaust aftertreatment systems on engines to reduce emissions isincreasing.

Generally, emission requirements vary according to engine type. Emissiontests for compression-ignition (diesel) engines typically monitor therelease of carbon monoxide (CO), unburned hydrocarbons (UHC), dieselparticulate matter (PM) such as ash and soot, and nitrogen oxides (NOx).Oxidation catalysts, such as diesel oxidation catalysts (DOC) have beenimplemented in exhaust gas aftertreatment systems to oxidize at leastsome particulate matter in the exhaust stream, reduce unburnedhydrocarbons and CO in the exhaust to less environmentally harmfulcompounds, and oxidize nitric oxide (NO) to form nitrogen dioxide (NO₂),which is used in the NOx conversion on an selective catalytic reduction(SCR) catalyst. To remove the particulate matter, a particulate matter(PM) filter is typically installed downstream from the oxidationcatalyst or in conjunction with the oxidation catalyst. However, someexhaust aftertreatment systems do not have a PM filter. With regard toreducing NOx emissions, NOx reduction catalysts, including SCR systems,are utilized to convert NOx (NO and NO₂ in some fraction) to N₂ andother compounds. Further, some systems include an ammonia oxidation(AMOX) catalyst downstream of the SCR catalyst to convert at least someammonia slipping from the SCR catalyst to N₂ and other less harmfulcompounds.

Exhaust aftertreatment system components can be susceptible to failureand degradation. Because the failure or degradation of components mayhave adverse consequences on the performance and emission-reductioncapability of the exhaust aftertreatment system, the detection and, ifpossible, correction of failed or degraded components is desirable. Infact, some regulations require on-board diagnostic (OBD) monitoring ortesting of many of the various components and performance of an exhaustaftertreatment system. When equipped on vehicles, most monitoring andtesting of aftertreatment system components and performance areperformed during on-road operation of the vehicle (e.g., while thevehicle is being driven on the road). Although such monitoring andtesting while the vehicle is in use may be convenient, the efficacy ofthe monitoring and testing diagnostic procedures, as well as anyrecovery procedures, are limited because the engine cannot be operatedoutside of a given on-road calibrated operating range. Additionally,because on-road operating demands typically have priority overdiagnostic and performance recovery procedures, the order, timing, andcontrol of such procedures may be less than ideal.

SUMMARY

One embodiment relates to an apparatus that includes a diagnostic enginecalibration module. The diagnostic engine calibration module isstructured to include a plurality of diagnostic processes for operatingan internal combustion engine system of an immobilized vehicle. Eachdiagnostic process is structured to bring the internal combustion enginesystem to one or more operating points prior to running a subsequentdiagnostic process to enable a diagnosis of a component of the internalcombustion engine system relating to the currently ran diagnosticprocess. The diagnostic engine calibration module is further structuredto control the order and timing of each diagnostic process in theplurality of diagnostic processes.

Another embodiment relates to internal combustion engine system,comprising an internal combustion engine system, and a controllercomprising memory designated for storage of an engine calibrationprogram and a diagnostic engine calibration program, the enginecalibration program structured to operate the internal combustion enginesystem while the internal combustion engine system is mobilized. Thediagnostic engine calibration program includes a plurality of diagnosticprocesses for operating the internal combustion engine system while theinternal combustion engine system is immobilized. The diagnosticprocesses include a diesel particulate filter (DPF) pressure faultprocess and a DPF ash restriction process. Each diagnostic process isstructured to bring the internal combustion engine system to one or moreoperating points prior to running a subsequent diagnostic process toenable a diagnosis of a component of the internal combustion enginesystem relating to the currently ran diagnostic process. The diagnosticengine calibration program is further structured to control the orderand timing of each diagnostic process in the plurality of diagnosticprocesses.

Still another embodiment relates to a method for diagnosing andconditioning an internal combustion engine system of a vehicle. Themethod includes immobilizing the vehicle in a controlled environment;removing a production engine calibration program from an electroniccontrol unit of the internal combustion engine system; uploading adiagnostic engine calibration program to the electronic control unit;running the diagnostic engine calibration program while the vehicle isimmobilized in the controlled environment, the diagnostic enginecalibration including a plurality of diagnostic processes for operatingan immobilized vehicle; removing the diagnostic engine calibrationprogram from the electronic control unit after completion of theplurality of commands; and uploading the production engine calibrationprogram to the electronic control unit. Each diagnostic process isstructured to bring the internal combustion engine system to one or moreoperating points prior to running a subsequent diagnostic process toenable a diagnosis of a component of the internal combustion enginesystem relating to the currently ran diagnostic process.

Yet another embodiment relates to an apparatus comprising a diagnosticengine calibration module structured to include a plurality ofdiagnostic processes for operating an internal combustion engine systemof a vehicle. Each diagnostic process is structured to bring theinternal combustion engine system to one or more operating conditionsprior to running a subsequent diagnostic process to enable a diagnosisof a component of the internal combustion engine system relating to thecurrently ran diagnostic process. The diagnostic engine calibrationmodule is structured to activate the plurality of diagnostic processesin the following order: a DPF pressure sensor fault process; a DPFpressure check fault process; a DEF deposit regeneration process; a DOCperformance test; a low NOx sensor rationality test; a SCR performancetest before an SCR regeneration event; an SCR performance test with anSCR regeneration event; a DPF ash restriction process; a high NOx sensorrationality test; a DOC and DPF temperature sensor rationality test; anda SCR temperature sensor rationality test.

The subject matter of the present application has been developed inresponse to the present state of the art, and in particular, in responseto the problems and needs in the exhaust aftertreatment systemdiagnostic and recovery art that have not yet been fully solved bycurrently available diagnostic and recovery techniques. Accordingly, thesubject matter of the present application has been developed to providemethods, systems, and apparatus for diagnosing the condition andrecovering the performance of exhaust aftertreatment system components.

In certain embodiments, the modules of the apparatus described hereinmay each include at least one of logic hardware and executable code, theexecutable code being stored on one or more memory devices. Theexecutable code may be replaced with a computer processor andcomputer-readable storage medium that stores executable code executed bythe processor.

Reference throughout this specification to features, advantages, orsimilar language does not imply that all of the features and advantagesthat may be realized with the subject matter of the present disclosureshould be or are in any single embodiment. Rather, language referring tothe features and advantages is understood to mean that a specificfeature, advantage, or characteristic described in connection with anembodiment is included in at least one embodiment of the presentdisclosure. Thus, discussion of the features and advantages, and similarlanguage, throughout this specification may, but do not necessarily,refer to the same embodiment.

The described features, structures, advantages, and/or characteristicsof the subject matter of the present disclosure may be combined in anysuitable manner in one or more embodiments and/or implementations. Inthe following description, numerous specific details are provided toimpart a thorough understanding of embodiments of the subject matter ofthe present disclosure. One skilled in the relevant art will recognizethat the subject matter of the present disclosure may be practicedwithout one or more of the specific features, details, components,materials, and/or methods of a particular embodiment or implementation.In other instances, additional features and advantages may be recognizedin certain embodiments and/or implementations that may not be present inall embodiments or implementations. Further, in some instances,well-known structures, materials, or operations are not shown ordescribed in detail to avoid obscuring aspects of the subject matter ofthe present disclosure. The features and advantages of the subjectmatter of the present disclosure will become more fully apparent fromthe following description and appended claims, or may be learned by thepractice of the subject matter as set forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic of an engine system including an aftertreatmentsystem according to an example embodiment.

FIG. 2 is a schematic of a controller for an engine system according toan example embodiment.

FIG. 3 is a schematic of a diagnostic engine calibration module for thecontroller of FIG. 2 according to an example embodiment.

FIG. 4 is a method for diagnosing and reconditioning an engine systemaccording to an example embodiment.

DETAILED DESCRIPTION

Referring to the figures generally, systems and methods oftroubleshooting an engine system are shown according to various exampleembodiments. According to the present disclosure, a calibration programis structured to be applied to an engine control module (“ECM”). Uponapplication, the calibration program, via the ECM, causes one or moreintrusive diagnostic tests. The diagnostic tests are structured to causethe engine to operate at various operating parameters. The diagnostictests allow a technician to trouble shoot the aftertreatment systemefficiently and quickly. Moreover, the diagnostic tests allow thetechnician to quickly diagnose which component(s) of the aftertreatmentsystem are malfunctioning or about to malfunction. This enables arelatively faster turnaround for repair sessions for the aftertreatmentsystem, which may save the customer time and money. After completion ofthe diagnostic session, the calibration program is removed from the ECM,such that the ECM operates according to the pre-existing engine setpoints thereafter.

As used herein, the term “intrusive” (in regard to performing one ormore diagnostic tests) is used to refer to operating the engine of thevehicle outside of various preset engine operating points (e.g., theremay be a limit on the maximum engine speed). More specifically,“intrusive diagnostic tests” refer to overriding various set engineoperating points to perform the tests. For example, many engineoperating points are set to be in compliance with one or more vehicularlaws (e.g., emissions). By overriding one or more of these operatingpoints, the engine may be forced into non-compliance with one or morevehicular laws. As described herein, a calibration program is uploadedinto the ECM of the vehicle to cause operation of the intrusivediagnostics tests. These tests allow for the efficient diagnosis ofvarious components of the engine system (to determine which one, if any,needs to be repaired, replaced, or otherwise inspected).

FIG. 1 depicts one embodiment of an engine system 10. The maincomponents of the engine system 10 include an internal combustion engine20 and an exhaust aftertreatment system 22 in exhaust gas-receivingcommunication with the engine 20. The internal combustion engine 20 canbe a compression-ignited internal combustion engine, such as adiesel-fueled engine, or a spark-ignited internal combustion engine,such as a gasoline-fueled engine operated lean. Although not shown, onthe air intake side, the engine system 10 can include an air inlet,inlet piping, a turbocharger compressor, and an intake manifold. Theintake manifold includes an outlet that is operatively coupled tocompression chambers of the internal combustion engine 20 forintroducing air into the compression chambers.

Within the internal combustion engine 20, air from the atmosphere iscombined with fuel, and combusted, to power the engine. The fuel comesfrom a fuel tank (not shown) through a fuel delivery system including,in one embodiment, a fuel pump and common rail to the fuel injectors,which inject fuel into the combustion chambers of the engine 20. Fuelinjection timing can be controlled by the controller 100 via a fuelinjector control signal.

Combustion of the fuel and air in the compression chambers of the engine20 produces exhaust gas that is operatively vented to an exhaustmanifold (not shown). From the exhaust manifold, a portion of theexhaust gas may be used to power a turbocharger turbine. Theturbocharger turbine drives the turbocharger compressor, which maycompress at least some of the air entering the air inlet beforedirecting it to the intake manifold and into the compression chambers ofthe engine 20.

The exhaust aftertreatment system 10 includes the controller 100 (whichalso can form part of the overall engine system 10), a diesel particularfilter (DPF) 40, a diesel oxidation catalyst (DOC) 30, a selectivecatalytic reduction (SCR) system 52 with an SCR catalyst 50, and anammonia oxidation (AMOX) catalyst 60. The SCR system 52 further includesa reductant delivery system that has a diesel exhaust fluid (DEF) source54 that supplies DEF to a DEF doser 56 via a DEF line 58.

In an exhaust flow direction, as indicated by directional arrow 29,exhaust gas flows from the engine 20 into inlet piping 24 of the exhaustaftertreatment system 22. From the inlet piping 24, the exhaust gasflows into the DOC 30 and exits the DOC into a first section of exhaustpiping 28A. From the first section of exhaust piping 28A, the exhaustgas flows into the DPF 40 and exits the DPF into a second section ofexhaust piping 28B. From the second section of exhaust piping 28B, theexhaust gas flows into the SCR catalyst 50 and exits the SCR catalystinto the third section of exhaust piping 28C. As the exhaust gas flowsthrough the second section of exhaust piping 28B, it is periodicallydosed with DEF by the DEF doser 56. Accordingly, the second section ofexhaust piping 28B acts as a decomposition chamber or tube to facilitatethe decomposition of the DEF to ammonia. From the third section ofexhaust piping 28C, the exhaust gas flows into the AMOX catalyst 50 andexits the AMOX catalyst into outlet piping 26 before the exhaust gas isexpelled from the system 22. Based on the foregoing, in the illustratedembodiment, the DOC 30 is position upstream of the DPF 40 if present andthe SCR catalyst 50, and the SCR catalyst 50 is positioned downstream ofthe DPF 40 when present and upstream of the AMOX catalyst 60. However,in alternative embodiments, other arrangements of the components of theexhaust aftertreatment system 22 are also possible.

The DOC 30 can have any of various flow-through designs known in theart. Generally, the DOC 30 is configured to oxidize at least someparticulate matter, e.g., the soluble organic fraction of soot, in theexhaust and reduce unburned hydrocarbons and CO in the exhaust to lessenvironmentally harmful compounds. For example, the DOC 30 maysufficiently reduce the hydrocarbon and CO concentrations in the exhaustto meet the requisite emissions standards for those components of theexhaust gas. An indirect consequence of the oxidation capabilities ofthe DOC 30 is the ability of the DOC to oxidize NO into NO₂. In thismanner, the level of NO₂ exiting the DOC 30 is equal to the NO₂ in theexhaust gas generated by the engine 20 plus the NO₂ converted from NO bythe DOC. Accordingly, one metric for indicating the condition of the DOC30 is the NO₂/NOx ratio of the exhaust gas exiting the DOC.

In addition to treating the hydrocarbon and CO concentrations in theexhaust gas, the DOC 30 can also be used in the controlled regenerationof the DPF 40, SCR catalyst 50, and AMOX catalyst 60. This can beaccomplished through the injection, or dosing, of unburned HC into theexhaust gas upstream of the DOC 30. Upon contact with the DOC 30, theunburned HC undergoes an exothermic oxidation reaction which leads to anincrease in the temperature of the exhaust gas exiting the DOC 30 andsubsequently entering the DPF 40, SCR catalyst 50, and/or the AMOXcatalyst 60. The amount of unburned HC added to the exhaust gas isselected to achieve the desired temperature increase or targetcontrolled regeneration temperature.

The DPF 40 can be any of various flow-through designs known in the art,and configured to reduce particulate matter concentrations, e.g., sootand ash, in the exhaust gas to meet requisite emission standards. TheDPF 40 captures particulate matter and other constituents, and thusneeds to be periodically regenerated to burn off the capturesconstituents. Additionally, the DPF 40 may be configured to oxidize NOto form NO₂ independent of the DOC 30.

As discussed above, the SCR system 52 includes a reductant deliverysystem with a reductant (e.g., DEF) source 54, pump (not shown) anddelivery mechanism or doser 56. The reductant source 54 can be acontainer or tank capable of retaining a reductant, such as, forexample, ammonia (NH₃), DEF (e.g., urea), or diesel oil. The reductantsource 54 is in reductant supplying communication with the pump, whichis configured to pump reductant from the reductant source to thedelivery mechanism 56 via a reductant delivery line 58. The deliverymechanism 56 is positioned upstream of the SCR catalyst 50. The deliverymechanism 56 is selectively controllable to inject reductant directlyinto the exhaust gas stream prior to entering the SCR catalyst 50.

In some embodiments, the reductant can either be ammonia or DEF, whichdecomposes to produce ammonia. The ammonia reacts with NOx in thepresence of the SCR catalyst 50 to reduce the NOx to less harmfulemissions, such as N₂ and H₂O. The NOx in the exhaust gas streamincludes NO₂ and NO. Generally, both NO₂ and NO are reduced to N₂ andH₂O through various chemical reactions driven by the catalytic elementsof the SCR catalyst in the presence of NH₃. However, as discussed above,the chemical reduction of NO₂ to N₂ and H₂O typically is the mostefficient chemical reaction. Therefore, in general, the more NO₂ in theexhaust gas stream compared to NO, the more efficient the NO_(x)reduction performed by the SCR catalyst. Accordingly, the ability of theDOC 30 to convert NO to NO₂ directly affects the NOx reductionefficiency of the SCR system 150. Put another way, the NOx reductionefficiency of the SCR system 52 corresponds at least indirectly to thecondition or performance of the DOC 30. However, primarily, the NOxreduction efficiency of the SCR system 52 corresponds with the conditionor performance of SCR catalyst 50.

The SCR catalyst 50 can be any of various catalysts known in the art.For example, in some implementations, the SCR catalyst 50 is avanadium-based catalyst, and in other implementations, the SCR catalystis a zeolite-based catalyst, such as a Cu-Zeolite or a Fe-Zeolitecatalyst. In one representative embodiment, the reductant is aqueousurea and the SCR catalyst 50 is a zeolite-based catalyst.

The AMOX catalyst 60 can be any of various flow-through catalystsconfigured to react with ammonia to produce mainly nitrogen. Generally,the AMOX catalyst 60 is utilized to remove ammonia that has slippedthrough or exited the SCR catalyst 60 without reacting with NO_(x) inthe exhaust. In certain instances, the aftertreatment system 22 can beoperable with or without an AMOX catalyst. Further, although the AMOXcatalyst 60 is shown as a separate unit from the SCR catalyst 52, insome implementations, the AMOX catalyst can be integrated with the SCRcatalyst, e.g., the AMOX catalyst and the SCR catalyst can be locatedwithin the same housing. The condition of the AMOX catalyst 60 can berepresented by the performance of the AMOX catalyst (i.e., the abilityof the AMOX catalyst to convert ammonia into mainly nitrogen).

Various sensors, such as NOx sensors 12, 14 and temperature sensors 16,18, may be strategically disposed throughout the exhaust aftertreatmentsystem 22 and may be in communication with the controller 100 to monitoroperating conditions of the engine system 10. In one embodiment, the NOxsensor 12 is positioned upstream of the SCR catalyst 50 and configuredto detect the concentration of NOx in the exhaust gas upstream of theSCR catalyst (e.g., entering the SCR catalyst). In the presentembodiment, the upstream NOx sensor 12 is positioned upstream of the DOC30, but in other embodiments, the upstream NOx sensor 12 can bepositioned at any of various locations upstream of the SCR catalyst 50.The NOx sensor 14 is positioned downstream of the SCR catalyst 50 andconfigured to detect the concentration of NOx in the exhaust gasdownstream of the SCR catalyst (e.g., exiting the SCR catalyst). In thepresent embodiment, the downstream NOx sensor 14 is positioneddownstream of the AMOX catalyst 60 (e.g., at a tailpipe of the system),but in other embodiments, the downstream NOx sensor may be positionedupstream of the AMOX catalyst 60.

The temperature sensors 16 are associated with the DOC 30 and DPF 40,and thus can be defined as DOC/DPF temperature sensors 16. The DOC/DPFtemperature sensors are strategically positioned to detect thetemperature of exhaust gas flowing into the DOC 30, out of the DOC andinto the DPF 40, and out of the DPF before being dosed with DEF by thedoser 56. The temperature sensors 18 are associated with the SCRcatalyst 50 and thus can be defined as SCR temperature sensors 18. TheSCR temperature sensors 18 are strategically positioned to detect thetemperature of exhaust gas flowing into and out of the SCR catalyst 50.

Although not shown, the engine system 10 and exhaust aftertreatmentsystem 22 includes many other types of sensors for detecting othercharacteristics of the system at various locations throughout thesystems. Also, the systems 10, 22, including the controller 100, mayinclude various virtual sensors for estimating various characteristicsof the system.

Although the exhaust aftertreatment system 22 shown includes one of anDOC 30, DPF 40, SCR catalyst 50, and AMOX catalyst 60 positioned inspecific locations relative to each other along the exhaust flow path,in other embodiments, the exhaust aftertreatment system may include morethan one of any of the various catalysts positioned in any of variouspositions relative to each other along the exhaust flow path as desired.Further, although the DOC 30 and AMOX catalyst 60 are non-selectivecatalysts, in some embodiments, the DOC and AMOX catalyst can beselective catalysts.

The controller 100 controls the operation of the engine system 10 andassociated sub-systems, such as the internal combustion engine 20 andthe exhaust gas aftertreatment system 22. The controller 100 is depictedin FIGS. 1 and 2 as a single physical unit, but can include two or morephysically separated units or components in some embodiments if desired.Generally, the controller 100 receives multiple inputs 114, processesthe inputs, and transmits multiple commands or outputs. The multipleinputs 114 may include sensed measurements, from the sensors, estimatesfrom virtual sensors, and various user inputs. The inputs 114 areprocessed by the controller 100 using various algorithms, stored data,and other inputs to update the stored data and/or generate outputvalues. The generated output values and/or commands are transmitted toother components of the controller and/or to one or more elements of theengine system 10 to control the system to achieve desired results.

Generally, the controller 100 includes various modules for controllingthe operation of the engine system 10. For example, the controller 100includes memory reserved for an engine calibration module 110 containingcalibrated instructions for operation of the engine system 10. As isknown in the art, the controller 100 and its various modular componentsmay comprise processor, memory, and interface modules that may befabricated of semiconductor gates on one or more semiconductorsubstrates. Each semiconductor substrate may be packaged in one or moresemiconductor devices mounted on circuit cards. Connections between themodules may be through semiconductor metal layers,substrate-to-substrate wiring, or circuit card traces or wiresconnecting the semiconductor devices.

Referring to FIG. 2, the controller 100, which can be the electroniccontrol module (ECM) or electronic control unit (ECU) of a vehicle,includes memory reserved for an engine calibration module 110 or programwith instructions for operating the engine system 10. When executed, theengine calibration module 110 generates engine control commands 112 foractuating the various components of the engine system 10 necessary foroperation of the engine system according to the engine calibration setby the module. The engine calibration module 110 also receives inputs114 from various sources, such as one or more of the plurality ofsensors of the engine system 10, and user input, such as actuation of anaccelerator pedal or activation of an auxiliary system, and providesdiagnostic outputs 116.

As used herein, the term “calibration module” refers to stored operationparameters that are mostly permanent. They are mostly permanent becauseend-users are usually prevented from adjusting the operation parametersstored in the calibration module (i.e., the calibration parameters). Forreference, in comparison, an adjustable operation parameter may includethe cruise set-speed, which is adjustable by an end user. In regard backto the calibration module parameters, the original equipmentmanufacturer (“OEM”) can usually adjust them. Accordingly, theseparameters are usually engineering-type parameters and/or closely-heldOEM parameters (e.g., a maximum power output of the engine). Accordingto the present disclosure, the diagnostic engine calibration module 130includes commands to cause the diagnostic tests described herein to beintrusive, such that one or more engineering-type and/or closely-heldOEM parameters are overridden during operating of the commands.

As such, the engine calibration module 110 may include instructions thatcause the otherwise permanent operation parameters (i.e., theengineering-type and/or closely-held OEM set parameters) to beoverridden. Thus, as mentioned above, in one embodiment, the enginecalibration module 110 is structured as an intrusive diagnostics module(as opposed to a non-intrusive diagnostics module, where the commandsfor operating the engine system do not cause the engine to operateoutside of the mostly permanent operation set points of the enginesystem). By overriding these set points, the engine may operate outsideof various vehicular laws and/or on-road standards (e.g., cause anunacceptable amount of emissions). As an example, take a usuallypermanent parameter: the commands of the vehicle operator (e.g.,depression of the accelerator pedal) are always obeyed by the controller(e.g., ECM). However, the engine calibration module 110 may overridethis permanent parameter to perform its stored operations and disregardthe commands from the operator (hence, intrusive). This type of controlmay be illegal if used on a road (i.e., outside the service bay) due tothe operations of the module 110 not being able to react to otherdrivers and/or obey posted laws.

Referring now back to FIG. 2, prior to use by an end-user, a productionengine calibration module 120 is uploaded to the controller 100 andsaved in the memory reserved for the engine calibration module 110. Inessence, after being uploaded, the production engine calibration module120 becomes the engine calibration module 110 for operation of theengine system 10. The production engine calibration module 120 includesinstructions that are specifically calibrated for operating the enginesystem 10 under normal on-road operation of the vehicle housing theengine system. Accordingly, the production engine calibration module 120calibrates the engine system 10 to meet engine production standards orregulations set by regulatory agencies. In other words, the operatingparameters or conditions of the engine system 10 are purposefullylimited in order to comply with various standards associated with normalon-road use of the vehicle, such as emissions standards, fuelconsumption standards, temperature standards, and on-board diagnostic(“OBD”) standards. Therefore, although the production engine calibrationmodule 120 may include instructions for conducting diagnostic testing ofthe engine system 10, the operating parameters of the diagnostic testsare constrained due to the need for compliance with the regulated normalon-road standards. Similarly, although the production engine calibrationmodule 120 may include instructions for conducting recondition orrecovery processes (e.g., regeneration events) for reconditioning orrecovering the performance of various components of the engine system10, the efficacy of the processes may be limited due to the constraintsimposed by the necessary compliance with the regulated normal on-roadstandards. As mentioned above, these are the mostly permanent operatingparameters that are set by the calibration module 120.

After delivery to an end-user, and likely after some use of the vehicleby the end-user, the vehicle may be immobilized or rendered stationary(e.g., maintained in park or out-of-gear) for a variety of reasons. Forexample, the vehicle may be brought into a service bay for scheduled ornon-scheduled maintenance (e.g., repairs). While in the service bay, thevehicle remains immobilized, while the engine system 10 of the vehicleremains operational. In this manner, and because the vehicle ismaintained in the controlled environment of the service bay (i.e., thevehicle is not being operated on the road), the operation of the vehicleis not constrained by the regulated normal on-road standards.

While in the service bay, whether before or after the maintenance isperformed, the production engine calibration module 120 is removed ordeleted from the controller 100, and is replaced by the diagnosticengine calibration module 130 as the engine calibration module 110 ofthe controller, which allows for the intrusive diagnostic tests(described herein) to be performed. Although not shown, a diagnostictool can be coupled in data transmitting communication with thecontroller 100 via a data communication link or bus. The diagnostic toolcan be configured to delete or command deletion of the production enginecalibration module 120 from the memory reserved for the enginecalibration module 110. Alternatively, the diagnostic tool can remove acopy of the production engine calibration module 120, as indicated bybi-directional arrows in FIG. 2, and store the production enginecalibration module 120 on the tool.

After the production engine calibration module 120 is deleted or removedby the tool, the tool can be used to upload the diagnostic enginecalibration module 130 into the memory reserved for the enginecalibration module 110. In this manner, the original production enginecalibration module 120 is replaced by the diagnostic engine calibrationmodule 130. The diagnostic engine calibration module 130 includesinstructions that are specifically calibrated for operating the enginesystem 10 under a dedicated diagnostic operation of the vehicle housingthe engine system. The instructions include one or more diagnosticprocesses that are structured to bring the internal combustion enginesystem to one or more operating conditions prior to performance of asubsequent diagnostic process to enable diagnosis of a component in theinternal combustion engine system relating to the currently randiagnostic process. As mentioned above, because operation of the vehicleis free of regulated constraints in the controlled environment of theservice bay, the dedicated diagnostic operation of the vehicle andengine system 10 utilizes operating conditions not otherwise allowedduring normal on-road use of the vehicle for achieving more accurate andefficient diagnostic and reconditioning results. When the diagnostic andreconditioning processes of the diagnostic engine calibration module 130are complete, the diagnostic engine calibration module 130 is removedfrom the controller 100 (e.g., either deleted or a copy is removed, asindicated by bi-directional arrows in FIG. 2) and replaced by theproduction engine calibration module 120 via operation of the tool.After the production engine calibration module 120 is uploaded back intothe memory reserved for the engine calibration module 110, the vehicleand engine system 10 is equipped to return to normal on-road operatingconditions (i.e., engine system operation within the previously existingmostly permanent operation parameters of the production enginecalibration module 120).

Referring to FIG. 3, the diagnostic engine calibration module 130includes a plurality of modules each configured with instructions toautomatically execute one or more diagnostic or reconditioning processeswithout user input. Additionally, the diagnostic engine calibrationmodule 130 includes logic to automatically and sequentially control theorder and timing (i.e., start and end) of the diagnostic andreconditioning processes executed by the modules. In other words, oncethe diagnostic engine calibration module 130 is installed and initiated,the diagnostic and reconditioning processes run automatically withoutuser intervention (e.g., a driver is not controlling operation of thevehicle). The diagnostic engine calibration module 130 generates theengine control commands 112 that actuate the components of the enginesystem 10. In one embodiment, the diagnostic engine calibration module130 is an intrusive diagnostics tool, such that the commands cause anoverride of otherwise-set engine operating parameters (e.g., maximumpower output). Accordingly, one or more of the tests described herein(in regard to the modules) may also be intrusive. The diagnostic enginecalibration module 130 may also provide diagnostic outputs 116 that mayinclude indications of the conditions or health of the engine system 10,and its various components, and a prediction of the remaining life ofsuch components.

The modules (and accompanying diagnostic processes) of the diagnosticengine calibration module 130 may now be described. According to oneexample, the diagnostic processes are arranged in the following order ofoperation: 1) DPF pressure sensor fault process while the ECM is on andthe engine is off; 2) DPF pressure check fault process while the engineand ECM are on; 3) a DEF deposit regeneration process; 4) DOCperformance process; 5) a low NOx sensor rationality test; 6) a SCRperformance test before an SCR regeneration; 7) an SCR performance testafter an SCR regeneration event (e.g., desulfurization (DeSOx)); 8) ifan SCR fault is received, perform a doser diagnostic test; 9) DPF ashrestriction test; 10) a high NOx sensor rationality test; and 11)compare DOC/DPF thermistors to one another, compare SCR thermistors toone another, and perform another NOx sensor rationality test.

This example order of operations allows the diagnosis (malfunctioning,potentially malfunctioning, and/or correctly function) of one or morecomponents in the internal combustion engine system (including theexhaust aftertreatment system). The example order of operations may bebriefly explained as follows.

The DPF pressure check fault process is performed when the engine is off(but the ECM is on) and then when the engine is on (processes 1-2). Whenthe engine is off, no air should be moving through the engine such thatthe pressure sensor reading (differential across the DPF) is near zero.When the engine is on, the sensor (or sensors) should measure asubstantially greater pressure difference across the DPF. This may bepreset to determine whether the DPF is functioning correctly. In oneembodiment, when the engine is turned on, the engine will accelerate toapproximately 1800 revolutions-per-minute. A decomposition reactor(converts diesel exhaust fluid into ammonia) is allowed to burn dieselexhaust fluid deposits (i.e., DEF deposit regeneration process, process3). During the burn, the DOC performance may be monitored (process 4).Because of the high engine speed, a higher flow rate is going throughthe exhaust aftertreatment system, which makes determining potentialissues with the DOC easier. In one embodiment, the fan is locked duringthis process and a fault code is set to trigger if the thermostat isleaking. Process 3 enables the diagnosis of the DOC. In someembodiments, as described below, a DOC recondition process is alsoperformed (which would occur here, before process 5). At process 5, alow NOx sensor test is performed; usually, this test is performed at 100ppm NOx (low NOx module 208). At processes 6 and 7, an SCR performancetest may be performed before and after an SCR regeneration event (e.g.,DeSOx). The performance test may be run at approximately 350 g/s exhaustflow and 350° C. exhaust temperatures. These processes may enablediagnosis of the SCR component. At process 8, if an SCR fault isreceived (i.e., the SCR is not performing according to various presetparameters, possibly embodied in one or more fault codes), a doserdiagnostic test may be performed. The doser diagnostic test is a test tocheck the flow rate of the doser (i.e., of the reductant through thedoser/injector). Thus, one or more flow sensors may be used with thedoser 56 that monitor the flow rate of a reductant through the doser.Because the fuel doser/injector can plug up with carbon, the doserdiagnostic test is performed to ensure a proper flow rate through thedoser/injector. The doser diagnostic test may also include measuring thechange in pressure across a fixed orifice size of the injector. If thechange in pressure is above (in some embodiments, below) a predeterminedthreshold, this may indicate that the doser/injector is plugged orclogged with carbon and needs to be replaced or serviced. At process 9,a DPF ash restriction test may be performed. A fault code may betriggered if too much ash is detected. Accordingly, the DPF is beingdiagnosed at process 9. After this test, the engine may be run at 1600revolutions-per-minute (a relatively high speed for acompression-ignition engine (diesel) that equates to a relatively higherexhaust flow rate). At process 10, a high NOx sensor test is performed(e.g., 1000 ppm NOx). After a predetermined amount of time (e.g., fiveminutes) at the preset engine speed (e.g., 1600 revolutions-per-minute),the engine may HC doser purge. After this, the engine may idle foranother amount of predetermined amount of time (e.g., five minutes).Upon completion, at process 11, the DOC/DPF thermistors are compared toone another, the SCR thermistors to one another, and (in someembodiments) a third NOx sensor rationality test is performed. In oneexample configuration, a fault code is triggered if the DOC/DPFthermistors are outside of +/−25° C. of each other. In another exampleconfiguration, a fault code is triggered if the SCR thermistors areoutside of +/−25° C. of each other. After these two checks, the enginemay return to idle. At idle, the NOx sensors may be left on for a littlewhile longer (adjustable). In one example, a service technician maydatalog the NOx sensor reading after removing the NOx sensor from thesystem and letting it hang out in the open.

As can be seen, this order of operations allows the diagnosis of one ormore components in the exhaust after treatment system. This order may berearranged in other embodiments. The above is a brief overview of thediagnostic processes of the diagnostic engine calibration module 130.The details of these processes may be more fully described in regard tothe sub-modules of the diagnostic engine calibration module 130.

The DPF pressure module 200 is structured to perform a DPF pressurecheck fault process. In this process, the module 200 is configured toset the fault thresholds for the pressure differential across the DPF 40and the DPF outlet pressure. Because the diagnostic and reconditioningprocesses executed by the modules of the diagnostic engine calibrationmodule 130 are performed on an immobilized vehicle in a controlled orcontained environment, the fault thresholds for the DPF pressuredifferential and DPF outlet pressure are tighter or less conservative(e.g., threshold values are within a smaller range) than with diagnosticprocesses associated with normal on-road operation of the vehicle. TheDPF pressure module 200 sets the DPF pressure differential and DPFoutlet pressure fault thresholds upon activation of the diagnosticengine calibration module 130, which may occur upon start-up of theengine. Thus, the technician may monitor the pressure difference acrossthe DPF 40 while the engine is on and the ECM is on. If the pressuredifferential is above a predetermined maximum amount, this may indicatethat the DPF is not removing enough particles (i.e., too high of flowrate). If the pressure differential is below a predetermined minimumamount, this may indicate that the filter is full of particles and theexhaust flow is restricted (i.e., the filter may need to be replaced orcleaned). In this event, a DPF ash restriction test may be utilized(described herein).

In one example, the DPF pressure module 200 is structured to perform aDPF pressure sensor fault process. This process includes activating theECM while the internal combustion engine system remains off. In theseoperating conditions, the internal combustion engine is not moving airthrough the system (i.e., the DPF). Accordingly, the pressuredifferential across the DPF should be near zero. This test may indicatethe functioning of the pressure sensor (in some embodiments, pressuresensors) for the DPF. If the technician notices a pressure differentialnot in align with this expectation (may be based on a predeterminedpercentage difference from zero that is acceptable), the technician maybe alerted to a possible malfunction of the DPF and would be compelledto examine the DPF further. In one embodiment, the DPF pressure sensorfault process is structured to be performed prior to the DPF pressurecheck fault process.

The DEF deposit module 202 is configured to execute a regeneration eventof the exhaust aftertreatment system 22 to remove DEF deposits, as wellas soot and sulfur deposits, which may have formed within the system(process 3). Such a DEF regeneration event promotes a clean andrelatively DEF deposit free environment to conduct other diagnostic andreconditioning processes. In one implementation, the regeneration eventexecuted by the DEF deposit module 202 includes maintaining the enginespeed of the engine 20 at a relatively low desired engine speed (e.g.,about 900 RPM), increasing the temperature of the exhaust gas flowingthrough the system 22 to a desired temperature (e.g., about 525-650°C.), and disabling DEF dosing all for a predetermined amount of time.The particular conditions of the DEF regeneration event executed by theDEF deposit module 202 are not conducive to, and may not be allowableduring, normal on-road operation of the vehicle. This is based on theintrusive nature of the test. For example, during normal on-roadoperation of the vehicle, exhaust gas temperatures reaching about525-650° C. and disabling DEF dosing may prevent the engine system 10from meeting emissions standards. However, because meeting emissionsstandards is not a concern in the immobilized, controlled environment,the particular conditions of the DEF regeneration event can be tuned tomore effectively remove DEF and other deposits within the systemcompared to normal on-road regeneration events. As mentioned above, inone embodiment, this regeneration event occurs after the SCR activitycheck.

The DOC performance module 204 is configured to monitor and evaluate theperformance of the DOC 30, and recondition the DOC if necessary. Theoperating conditions of the DOC performance test and reconditiondiagnostic executed by the DOC performance module 204 are also intrusivetests, which may not be acceptable during normal on-road operatingconditions. Relatively high temperatures and high NOx may act torecondition the DOC. The high NOx and high temperatures may beaccomplished via adjustment to the EGR fraction and/or the start ofinjection (e.g., injection timing). This test utilizes the hightemperature and high flow to clean the soot, fuel, and/or Sulfur fromthe DOC. The DOC performance module 204 may also enable monitoring ofthe health of the DOC. In one embodiment, the DOC performance module 204is structured to turn on HC dosing. This inhibits the NO₂ reaction inthe DOC. From this and the NOx conversion rate, differentiation ispossible between the DOC's health to NO₂ conversion versus thehydrocarbon conversion rate. Accordingly, the oxidation rate of NO toNO₂ may be monitored as a function of HC dosing to determine whether theconversion rate is within predetermined acceptable standards.

The NOx sensor module 206 includes several sub-modules each associatedwith a separate diagnostic test associated with the NOx sensors 12, 14of the engine system 10. Following the DOC performance and reconditiondiagnostic of the DOC performance module 204, the low NOx module 208 ofthe NOx sensor module 206 is configured to perform a rationality checkof the NOx sensors 12, 14 at a relatively low concentration of engineout NOx (e.g., between about 75 ppm and about 100 ppm, where “ppm”stands for parts-per-million). Moving the start of injection or theamount of EGR fract can achieve this. Accordingly, the NOx sensor errormay be represented as a function of NOx ppm. The low NOx rationalitycheck includes disabling DEF dosing, determining the difference betweenthe NOx concentrations detected by the SCR upstream and downstream NOxsensors 12, 14, setting fault thresholds for the NOx within a relativelytight range, and comparing the NOx concentration difference with thefault thresholds. Such a low NOx rationality check cannot be performedduring normal on-road operation of the vehicle as disabling DEF dosingmay prevent the engine system 10 from meeting emissions standardsrequired during normal on-road operation.

The SCR regeneration module 214 is configured to thermally andchemically regenerate the SCR catalyst 50 to remove sulfur deposits(DeSOx) from the SCR catalyst. In one implementation, the SCRregeneration event commanded by the SCR regeneration module 214 includeselevating or maintaining the exhaust gas temperature at an elevatedlevel and reducing or maintaining the engine speed at a reduced levelfor a desired period of time.

After the SCR catalyst 50 has been regenerated to remove sulfurdeposits, the SCR performance module 216 conducts a performance test ofthe regenerated SCR catalyst 50. In one implementation, the SCRperformance test includes increasing the engine speed to a desiredhigher engine speed (e.g., 1,800 RPM) and maximizing the exhaust flowrate by closing EGR valves and manipulating the characteristics of aturbocharger. More specifically, the SCR performance test includesallowing the turbocharger to pump all the air by closing the EGR valveand pinching down the variable geometry turbocharger. The fuelinginjectors are manipulated in such a way that helps build boost andcreate heat for the exhaust system. In one example, once the DOC'shardware limit of 250° C. of exhaust gas temps is surpassed (intrusivenature of the test), the fuel doser is enabled to dose fuel into theexhaust. Once this happens, almost any exhaust temperature may betargeted. Generally, the exhaust temperature is chosen to be between 400and 650° C., depending on what test is being performed. Some tests maynot use the fuel doser, to keep exhaust temps low. With all thesedifferent temperatures and flows available, the SCR system heath may bemapped to compare to OBD/EPA regulations to estimate the percent liferemaining or if a part should be replaced. Within this test, the mostlikely cause of the performance shift, for example if the DOC NO₂conversion is low or the SCR is degraded, or if simply the AMOx isdegraded may be identified to make the best repair possible.Essentially, the SCR performance test monitors the NOx conversionefficiency of the SCR catalyst 50 by comparing the NOx concentrationreadings from the upstream and downstream NOx sensors 12, 14.Additionally, the NOx conversion efficiency of the SCR catalyst 50 istested at various DEF dosing rates (e.g., 1.0, 2.0, 3.0 ammonia-to-NOxratios). Preferably, the SCR performance test is conducted automaticallyby the SCR performance module 216, but in some instances, the SCRperformance test can be conducted manually.

In another example embodiment, at stand-alone emissions measurementchart may be utilized with this test. Accordingly, this test would notutilize an engine sensor. Rather, some other stand-alone sensor for NOx,O₂, CO, exhaust flow, and the like would be utilized with the SCRperformance test.

The SCR performance module 216 may also trigger an SCR fault should theperformance of the SCR catalyst 50 drop below a minimum NOx conversionefficiency. If the SCR fault is triggered, the SCR performance module216 may include additional modules that conduct a DEF testing todetermine if the DEF delivery system 52 is malfunctioning and/or theconcentration of DEF is low, which may indicate the DEF is diluted. Inregard to the concentration of DEF being low, there may be three maincauses: 1) A piece of hardware could be bad, such as the SCR, DOC or NOxsensor; 2) The DEF may not be at the proper concentration, in which amanual test can be conducted (e.g., a refractometer may be used); or 3)The DEF may not be pumping into the system, which means there may be akink, a suction side leak pumping air instead of DEF, or an externalleak. In one embodiment, items 2 and 3 must be checked out before apiece of hardware may be said to have failed. Additionally, if an SCRfault is triggered, a doser diagnostic test may also be performed. Asmentioned above (process 8), the doser diagnostic test is used to checkthe flow rate through the doser. If the flow rate is insufficient (i.e.,below a predetermined threshold), the doser may be malfunctioning andthe correct exhaust temperatures may not be obtained. Accordingly,because the exhaust temperatures may not be achieved and insufficientreductant is being supplied, the NOx emissions may not be reduced to adesired level.

The DPF ash restriction module 218 is configured to conduct an ashrestriction test of the DPF 40. During the regeneration events conductedby the DEF deposit module 202 and SCR regeneration module 214, the sooton the DPF 40 is removed. However, the regeneration events may notremove some species of ash from the DPF 40, such that ash may remaincaked on the surface of the DPF following the regeneration events.Accordingly, the DPF ash restriction module 218 conducts the ashrestriction test to determine the amount of ash that remains on the DPF40 and triggers a fault if the amount of ash meets an upper threshold.In one embodiment, the DPF ash restriction process includes performing apressure differential check across the DPF at a relatively high exhaustflow rate after a regeneration event of the DPF. This ensures, orsubstantially ensures, that the soot is gone in the DPF.

After the DPF ash restriction test is completed, the high NOx module 210of the NOx sensor module 206 is configured to perform anotherrationality check of the NOx sensors 12, 14, but at a relatively highconcentration of engine out NOx (e.g., about 650 ppm) and higher enginespeed (e.g., 1,200 RPM). Like the low NOx rationality check, this highNOx rationality check includes disabling DEF dosing, determining thedifference between the NOx concentrations detected by the SCR upstreamand downstream NOx sensors 12, 14, setting fault thresholds for the NOxwithin a relatively tight range, and comparing the NOx concentrationdifference with the fault thresholds. Similar to the low NOx rationalitycheck, this high NOx rationality check cannot be performed during normalon-road operation of the vehicle as disabling DEF dosing may prevent theengine system 10 from meeting emissions standards required during normalon-road operation.

The thermostat failure module 220 of the diagnostic engine calibrationmodule 130 is configured to check the status of a thermostat of theengine system 10. The thermostat status check includes maintaining theengine system 10 in a steady state, such that the cooling system (notshown) of the engine system also is held in a steady state. With thecooling system in a steady state, the thermostat can be accuratelychecked for leakage, and a fault can be triggered should leakage bedetected. Such a steady-state thermostat check can be difficult, if notnearly impossible, to conduct under normal on-road operating conditionsbecause of the difficulty of an engine system operating under normalon-road conditions to reach a steady-state sufficiently long enough toaccurately detect leakage of the thermostat.

The diagnostic engine calibration module 130 further includes athermistor module 222 with a DOC/DPF module 224 and an SCR module 226.The DOC/DPF module 224 is configured to test the rationality of theDOC/DPF temperature sensors 16 and the SCR module 226 is configured totest the rationality of the SCR temperature sensors 18 (e.g., theDOC/DPF and SCR thermistors of process 11 described above). In oneimplementation, the DOC/DPF module 224 tests the rationality of theDOC/DPF temperature sensors 16 by maintaining the engine speed at arelatively higher speed (e.g., approximately 1,200 RPM to 1,600 RPM),maintaining the exhaust gas temperature at a moderate temperature (e.g.,200° C.), and maintaining the operations of the engine system 10 in asteady state. Under these conditions, the temperature readings of theDOC/DPF temperature sensors 16 are compared and a fault is triggered ifa difference between the temperature readings meets an upper threshold.Similarly, in one implementation, the SCR module 226 tests therationality of the SCR temperature sensors 18 by maintaining the enginespeed at a relatively higher speed (e.g., approximately 1,200 to 16,000RPM), maintaining the exhaust gas temperature at a moderate temperature(e.g., 200° C.), and maintaining the operations of the engine system 10in a steady state. Under these conditions, the temperature readings ofthe SCR temperature sensors 18 are compared and a fault is triggered ifa difference between the temperature readings meets an upper threshold.

In one example, regarding the DOC/DPF module 224 and the SCR module 226,the SCR and DOC/DPF temperature sensors are read after the engine hasbeen returned to an idle speed for a predetermined amount of time (e.g.,five minutes). In other words, in this example, the rationality of thesensors are checked by running the engine at a relatively higher speed,letting the engine idle for a predetermined amount of time, and thentaking one or more readings from the temperature sensors. The DOC/DPFtemperature sensors readings are compared to each other and the SCRtemperature sensor readings are compared to each other. If there is adifference between +/−25° C. in the readings, a fault may be triggered.In which case, one or more of the temperatures sensors may need to beserviced (repaired, replaced, checked again, etc.). Upon completion ofthese tests, the engine may return to an idle speed. At this point,(process 11 above) an additional NOx sensor rationality test may beperformed.

The ex situ module 212 of the NOx sensor module 206 is configured totake and analyze readings taken from a NOx sensor (e.g., one of NOxsensors 12, 14) removed from exhaust detecting communication with theexhaust aftertreatment system 22, but remaining in an operable conditionto detect NOx in the air outside of the exhaust aftertreatment system.Because air has at most negligible amounts NOx, any detection of NOx inthe air by the removed NOx indicates a faulty NOx sensor. In alternativeembodiments, the ex situ module 212 may be configured to facilitate theuse of an external NOx sensing system that is independent from the NOxsensors 12, 14 to aid in the detection of the rationality of any one ormore of the NOx sensors.

Finally, the diagnostic engine calibration module 130 includes an outputmodule 228 configured to receive the results of the diagnostic andreconditioning tests and processes executed by the modules, analyze theresults, and issue diagnostic outputs 116 representative of the results.In one implementation, the diagnostic outputs 116 includes an indicationof the remaining life of the components of the engine system, or thegeneral health of the components. Additionally, the diagnostic outputs116 may include indications of any failed or faulty components of thesystem that may require reconditioning or replacement.

Referring to FIG. 4, a method 300 for diagnosing and reconditioning anengine system is shown. In certain implementations, the steps of themethod 300 may be executed by the modules of the controller 100described above. The method 300 begins by immobilizing the vehicle inwhich an engine system is housed at 310. Immobilizing the vehicle mayinclude parking the vehicle in a service bay or other containedenvironment. The method 300 then includes deleting the production enginecalibration program from the ECU or ECM of the vehicle at 320. Theproduction engine calibration program may be the original enginecalibration program stored on the ECU during the initial production ofthe vehicle. After deleting the production engine calibration program,the method 300 includes uploading a diagnostic engine calibrationprogram to the ECU at 330 to effectively replace the deleted productionengine calibration program. In this manner, the engine system iseffectively recalibrated from a normal on-road operating mode conduciveto operation of the vehicle on the road to an abnormal diagnosticstationary operating mode not conducive to operation of the vehicle onthe road.

Following uploading of the diagnostic engine calibration program to theEDU, the method 300 runs the diagnostic engine calibration program at340. In one implementation, the initiation of the diagnostic enginecalibration program is triggered by user input, such as by holding theacceleration pedal down for a predetermined amount of time (e.g., 10seconds) or other means of user input. Running the diagnostic enginecalibration program at 340 include automatically and sequentiallyconducting the various tests, checks, and reconditioning processes ofthe modules of a diagnostic engine calibration module. The tests,checks, and reconditioning processes are conducted in a particularorder, one after the other, until all desired tests, checks, andreconditioning processes are completed. In some embodiments, running theentire diagnostic engine calibration program takes about an hour.Accordingly, a vehicle can be diagnosed and reconditioned during aroutine or non-routine maintenance appointment without addingsignificant down or wait time. According to one implementation, thediagnostic engine calibration program includes sequentially executingthe following processes in order: setting of DPF pressure faultthresholds, DEF deposit regeneration, DOC performance test, low NOxsensor rationality test, SCR catalyst regeneration, SCR catalystperformance test, DPF ash restriction test, high NOx sensor rationalitytest, thermostat failure check, DOC/DPF temperature sensor rationalitytest, SCR temperature sensor rationality test, and manual NOx sensorrationality test if desired. Of course, other diagnostic andreconditioning processes can be performed in place of or in addition tothose above.

After running the diagnostic engine calibration program at 340, themethod 300 includes generating an exhaust aftertreatment system statusat 350, which can include various outputs of the tests, estimates of thehealth of the components of the system, and/or predictions of theremaining life of the components of the system. After generating theexhaust aftertreatment system status at 350, the method 300 deletes orremoves the engine calibration program from the ECU at 360 and uploadsthe production engine calibration program back to the ECU. In essence,the production engine calibration program replaces the diagnostic enginecalibration program such that the engine system is effectivelyrecalibrated from the abnormal diagnostic stationary operating mode backto the normal on-road operating mode. Then, the method 300 includesmobilizing the vehicle at 380, which can include driving the vehiclefrom the contained environment or service bay back onto the road.

The schematic flow chart diagrams and method schematic diagramsdescribed above are generally set forth as logical flow chart diagrams.As such, the depicted order and labeled steps are indicative ofrepresentative embodiments. Other steps, orderings and methods may beconceived that are equivalent in function, logic, or effect to one ormore steps, or portions thereof, of the methods illustrated in theschematic diagrams.

Additionally, the format and symbols employed are provided to explainthe logical steps of the schematic diagrams and are understood not tolimit the scope of the methods illustrated by the diagrams. Althoughvarious arrow types and line types may be employed in the schematicdiagrams, they are understood not to limit the scope of thecorresponding methods. Indeed, some arrows or other connectors may beused to indicate only the logical flow of a method. For instance, anarrow may indicate a waiting or monitoring period of unspecifiedduration between enumerated steps of a depicted method. Additionally,the order in which a particular method occurs may or may not strictlyadhere to the order of the corresponding steps shown. It will also benoted that each block of the block diagrams and/or flowchart diagrams,and combinations of blocks in the block diagrams and/or flowchartdiagrams, can be implemented by special purpose hardware-based systemsthat perform the specified functions or acts, or combinations of specialpurpose hardware and program code.

Many of the functional units described in this specification have beenlabeled as modules, in order to more particularly emphasize theirimplementation independence. For example, a module may be implemented asa hardware circuit comprising custom VLSI circuits or gate arrays,off-the-shelf semiconductors such as logic chips, transistors, or otherdiscrete components. A module may also be implemented in programmablehardware devices such as field programmable gate arrays, programmablearray logic, programmable logic devices or the like.

Modules may also be implemented in machine-readable medium for executionby various types of processors. An identified module of executable codemay, for instance, comprise one or more physical or logical blocks ofcomputer instructions, which may, for instance, be organized as anobject, procedure, or function. Nevertheless, the executables of anidentified module need not be physically located together, but maycomprise disparate instructions stored in different locations which,when joined logically together, comprise the module and achieve thestated purpose for the module.

Indeed, a module of computer readable program code may be a singleinstruction, or many instructions, and may even be distributed overseveral different code segments, among different programs, and acrossseveral memory devices. Similarly, operational data may be identifiedand illustrated herein within modules, and may be embodied in anysuitable form and organized within any suitable type of data structure.The operational data may be collected as a single data set, or may bedistributed over different locations including over different storagedevices, and may exist, at least partially, merely as electronic signalson a system or network. Where a module or portions of a module areimplemented in machine-readable medium (or computer-readable medium),the computer readable program code may be stored and/or propagated on inone or more computer readable medium(s).

The computer readable medium may be a tangible computer readable storagemedium storing the computer readable program code. The computer readablestorage medium may be, for example, but not limited to, an electronic,magnetic, optical, electromagnetic, infrared, holographic,micromechanical, or semiconductor system, apparatus, or device, or anysuitable combination of the foregoing.

More specific examples of the computer readable medium may include butare not limited to a portable computer diskette, a hard disk, a randomaccess memory (RAM), a read-only memory (ROM), an erasable programmableread-only memory (EPROM or Flash memory), a portable compact discread-only memory (CD-ROM), a digital versatile disc (DVD), an opticalstorage device, a magnetic storage device, a holographic storage medium,a micromechanical storage device, or any suitable combination of theforegoing. In the context of this document, a computer readable storagemedium may be any tangible medium that can contain, and/or storecomputer readable program code for use by and/or in connection with aninstruction execution system, apparatus, or device.

The computer readable medium may also be a computer readable signalmedium. A computer readable signal medium may include a propagated datasignal with computer readable program code embodied therein, forexample, in baseband or as part of a carrier wave. Such a propagatedsignal may take any of a variety of forms, including, but not limitedto, electrical, electro-magnetic, magnetic, optical, or any suitablecombination thereof. A computer readable signal medium may be anycomputer readable medium that is not a computer readable storage mediumand that can communicate, propagate, or transport computer readableprogram code for use by or in connection with an instruction executionsystem, apparatus, or device. Computer readable program code embodied ona computer readable signal medium may be transmitted using anyappropriate medium, including but not limited to wireless, wireline,optical fiber cable, Radio Frequency (RF), or the like, or any suitablecombination of the foregoing

In one embodiment, the computer readable medium may comprise acombination of one or more computer readable storage mediums and one ormore computer readable signal mediums. For example, computer readableprogram code may be both propagated as an electro-magnetic signalthrough a fiber optic cable for execution by a processor and stored onRAM storage device for execution by the processor.

Computer readable program code for carrying out operations for aspectsof the present invention may be written in any combination of one ormore programming languages, including an object oriented programminglanguage such as Java, Smalltalk, C++ or the like and conventionalprocedural programming languages, such as the “C” programming languageor similar programming languages. The computer readable program code mayexecute entirely on the user's computer, partly on the user's computer,as a stand-alone computer-readable package, partly on the user'scomputer and partly on a remote computer or entirely on the remotecomputer or server. In the latter scenario, the remote computer may beconnected to the user's computer through any type of network, includinga local area network (LAN) or a wide area network (WAN), or theconnection may be made to an external computer (for example, through theInternet using an Internet Service Provider).

The program code may also be stored in a computer readable medium thatcan direct a computer, other programmable data processing apparatus, orother devices to function in a particular manner, such that theinstructions stored in the computer readable medium produce an articleof manufacture including instructions which implement the function/actspecified in the schematic flowchart diagrams and/or schematic blockdiagrams block or blocks.

The program code may also be loaded onto a computer, other programmabledata processing apparatus, or other devices to cause a series ofoperational steps to be performed on the computer, other programmableapparatus or other devices to produce a computer implemented processsuch that the program code which executed on the computer or otherprogrammable apparatus provide processes for implementing thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

Reference throughout this specification to “one embodiment,” “anembodiment,” or similar language means that a particular feature,structure, or characteristic described in connection with the embodimentis included in at least one embodiment of the present invention. Thus,appearances of the phrases “in one embodiment,” “in an embodiment,” andsimilar language throughout this specification may, but do notnecessarily, all refer to the same embodiment. Similarly, the use of theterm “implementation” means an implementation having a particularfeature, structure, or characteristic described in connection with oneor more embodiments of the present disclosure, however, absent anexpress correlation to indicate otherwise, an implementation may beassociated with one or more embodiments.

The present disclosure may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the disclosure is, therefore,indicated by the appended claims rather than by the foregoingdescription. All changes which come within the meaning and range ofequivalency of the claims are to be embraced within their scope.

What is claimed:
 1. An apparatus, comprising: a diagnostic enginecalibration module structured to include a plurality of diagnosticprocesses for operating an internal combustion engine system; whereineach diagnostic process is structured to bring the internal combustionengine system to one or more operating conditions prior to running asubsequent diagnostic process to enable a diagnosis of a component ofthe internal combustion engine system relating to the currently randiagnostic process; wherein one or more of the plurality of diagnosticprocesses cause the internal combustion engine system to operate outsideof one or more calibration parameters; and wherein the diagnostic enginecalibration module is further structured to control the order and timingof each diagnostic process in the plurality of diagnostic processes. 2.The apparatus of claim 1, wherein the plurality of diagnostic processesare structured to only operate the internal combustion engine system ofan immobilized vehicle.
 3. The apparatus of claim 1, wherein theplurality of diagnostic processes include at least one of a dieselparticulate filter (DPF) pressure sensor fault process; a DPF pressurecheck fault process; a diesel exhaust fluid (DEF) deposit regenerationprocess; a diesel oxidation catalyst (DOC) performance test; a low NOxsensor rationality test; a selective catalyst reduction (SCR)performance test before an SCR regeneration event; an SCR performancetest with an SCR regeneration event; a doser diagnostic test; a DPF ashrestriction process; a high NOx sensor rationality test; a DOC and DPFtemperature sensor rationality test; and a SCR temperature sensorrationality test.
 4. The apparatus of claim 3, wherein the DPF pressuresensor fault process includes measuring a pressure difference across adiesel particulate filter when an engine of the internal combustionengine system is turned off.
 5. The apparatus of claim 3, wherein theDPF pressure check fault process includes measuring a pressuredifference across a diesel particulate filter when an engine of theinternal combustion engine system is turned on.
 6. The apparatus ofclaim 3, wherein the DEF deposit regeneration process includes disablinga DEF dosing event for a predetermined amount of time, operating anengine of the internal combustion engine system at a relatively lowengine speed, and increasing a temperature of an exhaust gas to betweenabout 525° C. and 650° C.
 7. The apparatus of claim 3, wherein the DOCperformance test includes activating a DEF dosing event to monitor anoxidation rate of NO to NO₂ as a function of the DEF dosing.
 8. Theapparatus of claim 3, wherein the low NOx sensor rationality testincludes disabling a DEF dosing event, providing about 75 ppm to 100 ppmNOx out of the engine, and determining a NOx concentration across a SCRsystem, wherein the determined NOx concentration is compared against apredetermined fault threshold.
 9. The apparatus of claim 3, wherein theSCR performance test before an SCR regeneration event includessubstantially maximizing an exhaust gas flow rate, and monitoring a NOxconversion efficiency at various DEF dosing rates.
 10. The apparatus ofclaim 3, the SCR performance test with an SCR regeneration eventincludes elevating an exhaust gas temperature and reducing an enginespeed for a predetermined amount of time followed by substantiallymaximizing an exhaust gas flow rate, and monitoring a NOx conversionefficiency at various DEF dosing rates.
 11. The apparatus of claim 3,wherein the doser diagnostic test includes monitoring a flow rate of areductant through a doser.
 12. The apparatus of claim 3, wherein the DPFash restriction process includes determining an amount of ash thatremains on a diesel particulate filter and triggering a fault if theamount of ash meets an upper threshold.
 13. The apparatus of claim 3,wherein the high NOx sensor rationality test includes disabling a DEFdosing event, providing a relatively greater amount of NOx ppm out of anengine than in a low NOx sensor rationality test, operating the engineat a relative higher speed than during the low NOx sensor rationalitytest, and determining a NOx concentration across a SCR system, whereinthe determined NOx concentration is compared against a predeterminedfault threshold.
 14. The apparatus of claim 3, wherein the DOC and DPFtemperature sensor rationality test includes comparing DOC and DPFtemperature sensor readings to each other after an engine has run at anidle speed for a predetermined amount of time after running the engineat a relatively higher speed for another predetermined amount of time.15. The apparatus of claim 3, wherein the SCR temperature sensorrationality test includes comparing SCR temperature sensor readings toeach other after an engine has run at an idle speed for a predeterminedamount of time after running the engine at a relatively higher speed foranother predetermined amount of time.
 16. The apparatus of claim 1,wherein the diagnostic engine calibration module is uploaded to anelectronic control unit of a vehicle when the vehicle is immobilized andremoved from the electronic control unit prior to mobilization of thevehicle.
 17. An internal combustion engine system, comprising: acontroller comprising memory designated for storage of an enginecalibration program and a diagnostic engine calibration program, theengine calibration program structured to operate the internal combustionengine system while the internal combustion engine system is mobilized;wherein the diagnostic engine calibration program includes a pluralityof diagnostic processes for operating the internal combustion enginesystem while the internal combustion engine system is immobilized;wherein the diagnostic processes include: a DPF pressure sensor faultprocess; a DPF pressure check fault process; and a DPF ash restrictionprocess; wherein each diagnostic process is structured to bring theinternal combustion engine system to one or more operating conditionsprior to running a subsequent diagnostic process to enable a diagnosisof a component of the internal combustion engine system relating to thecurrently ran diagnostic process; and wherein one or more of theplurality of diagnostic processes cause the internal combustion enginesystem to operate outside of one or more calibration parameters.
 18. Thesystem of claim 17, wherein the DPF pressure sensor fault processincludes measuring a pressure difference across a diesel particulatefilter when an engine of the internal combustion engine system is turnedoff.
 19. The system of claim 17, wherein the DPF pressure check faultprocess includes measuring a pressure difference across a dieselparticulate filter when an engine of the internal combustion enginesystem is turned on.
 20. The system of claim 17, wherein the DPF ashrestriction process includes determining an amount of ash that remainson a diesel particulate filter and triggering a fault if the amount ofash meets an upper threshold.